Protective headgear and helmets have been used in a wide variety of applications and across a number of industries including sports, athletics, construction, mining, military defense, and others, to prevent damage to a user's head and brain. Damage and injury to a user can be prevented or reduced by helmets that prevent hard objects or sharp objects from directly contacting the user's head. Damage and injury to a user can also be prevented or reduced by helmets that absorb, distribute, or otherwise manage energy of an impact.
In addition to preventing or reducing damage or injury to the wearer of a helmet, conventional helmets have also included ventilation openings to allow for air circulation and airflow through a helmet. Ventilation and air circulation have increased comfort and allowed for temperature regulation and temperature mitigation for the user wearing the helmet. Conventional helmet ventilation openings have included ventilation openings that extend radially between an outer surface of the helmet and a center or cavity in the helmet for receiving a head of the helmet wearer.